Abstract:

The influencing characteristics and kinetics mechanisms of the degradation of coking wastewater by Fenton reagent have been studied. Based on small beaker tests,the influences of the factors,such as initial concentration of COD,H₂O₂ dosage,Fe²⁺ dosage,reaction temperature,etc. on the treatment effects are investigated. The results show that when the raw water COD is 260 mg/L,H₂O₂ dosage 666 mg/L,Fe²⁺ dosage 200 mg/L,and temperature 298 K,the COD removing rate reaches 89.53%. The empirical reaction kinetic model which reflects COD oxidation degradation in the initial stage fits the experimental data quite well. Therefore,the kinetics model can well predict the oxidation degradation situation of coking wastewater by using Fenton reagent. The total reaction series is 2.0017,among which the ranked reaction series of H₂O₂(0.5685) is higher than that of Fe²⁺(0.4940). It indicates that in the process of COD oxidation degradation by Fenton,the influence of initial H₂O₂ concentration is greater than that of Fe²⁺. The lower reaction activation energy indicates that Fenton reaction can be conducted more easily.

Key words: coking wastewater, Fenton oxidation, kinetics

摘要：

为研究Fenton试剂氧化降解焦化废水的影响特性及动力学机理，采用小试烧杯实验考察初始COD、H₂O₂投加量、Fe²⁺投加量和反应温度等因素对处理效果的影响。结果表明，原水COD为260 mg/L、H₂O₂投加量为666 mg/L、Fe²⁺投加量为200 mg/L、温度为298 K时，COD去除率达到89.53%；反应初始阶段COD氧化降解的表观反应动力学模型与实验数据得到较好的拟合，因此该动力学模型能较好地预测Fenton试剂对焦化废水的氧化降解情况；反应总级数为2.0017，其中H₂O₂的反应分级数（0.5685）高于Fe²⁺的反应分级数（0.4940），说明Fenton氧化降解COD过程中H₂O₂浓度的影响比Fe²⁺的大；较低的反应活化能说明反应较易进行。

关键词: 焦化废水, Fenton氧化, 动力学

CLC Number: 

• X703